The present invention relates to an improved D.C. power source for stabilizing an output voltage and/or current especially in integrated circuits (IC) and also for compensating for deviation or fluctuation in the current amplification factor h.sub.FE or .beta. of a transistor due to variation in the ambient temperature.
Heretofore, in a transistor circuit for supplying constant output voltage, a power supply voltage was divided by a pair of bias resistors including an emitter resistor in a transistor circuit built in an integrated circuit block, and the divided voltage was supplied to a transistor or transistors also built in the integrated circuit blocks. However, in a prior D.C. power source the compensation for preventing the change of the output voltage due to temperature change was not enough because the values of the resistances in the IC blocks were considerably varied by discrepancies among resistors as well as temperature variations, and it was very difficult to construct a transistor circuit in which an absolute value of the current flowing through a load was maintained constant.